Medium Of Exchange

Is this the Goldilocks of Exchanges? Not too large and not too small; just right. Actually, it's the other kind of medium, where it is a mechanism to facilitate trade using currency or any other object of value.

In old times, mediums of exchange used to be valuable items like gold or silver, or even the most valuable item of them all: salt (if only we could still trade the salt on our table for bars of gold). Without mediums of exchange, modern commerce wouldn't be possible. In order to get something you needed from someone else, you had to have something that they needed so you could barter with them. By creating mediums of exchanges, you didn't have to own something of usefulness, only something of value. Modern currencies act in the same way by facilitating trade without bartering.